RTC

The basic purpose for the RTC is to keep time of day. The other equally important purpose of RTC is for Digital Rights management. Some degree of tamper proofing is needed to ensure that simply stopping, resetting, or corrupting the RTC does not go unnoticed so that if this occurs, the application can re-acquire the time of day from a trusted source.

Features Supported 

Supported 15 bit 32768Hz counter.
Supported 48 bit seconds counter with +/- 1 30uS upto +/- 1 S drift adjustment every 4048 Seconds.
Support for 256 bits of Scratch PAD
1 ON_OFF compare event, 48-bits
1 OFF_ON compare event, 48-bits
2 event outputs OFF_ON and ON_OFF to CORE
Functional lockout, unlock by special vbusp sequence
HOST PROCESSOR can update MMRs without polling, thanks to HW Shadow/Auto Sync
HOST PROCESSOR can read time without polling, thanks to HW Shadow/Auto Sync

SysConfig Features 

Note

It is strongly recommend to use SysConfig where it is available instead of using direct SW API calls. This will help simplify the SW application and also catch common mistakes early in the development cycle.

RTC instance name
Input clock frequency to be used for RTC module
Enable Freeze Mode for RTC.
Enable Interrupt and Assign User Callback
Support to attach callback functions to each of the ON_OFF/OFF_ON events

Features NOT Supported 

PMIC enable support

Example Usage 

Include the below file to access the APIs 

#include <drivers/rtc.h>

Instance Open Example 

    RTC_Params         params;

    /* Initialize parameters */
    RTC_Params_init(&params);

    params.isfreezemode = true,
    params.onOffCallback = false,
    params.offOnCallback = false,

    /* Update object Parameters mode settings */
    gRTCObjects[CONFIG_RTC0].On_OffCallbackFunction = NULL,
    gRTCObjects[CONFIG_RTC0].Off_OnCallbackFunction = NULL,

    gRTCHandle = RTC_open(CONFIG_RTC0, &params);
    DebugP_assert(gRTCHandle != NULL);

Instance Close Example 

    RTC_close(gRTCHandle);

API Reference 

RTC Driver API/interface file.

RTC Timer Interrupt Set/Indication Flags

RTC_TMR_INT_INT0_STATUS_FLAG: ON_OFF status interrupt.

RTC_TMR_INT_INT1_STATUS_FLAG: OFF_ON status interrupt.

RTC_TMR_INT_INT0_CLEAR_FLAG: ON_OFF clear interrupt.

RTC_TMR_INT_INT1_CLEAR_FLAG: OFF_ON clear interrupt.

RTC_TMR_INT_INT0_SET_FLAG: ON_OFF set interrupt.

RTC_TMR_INT_INT1_SET_FLAG: OFF_ON set interrupt.

RTC_TMR_INT_INT0_RAW_STATUS_FLAG: ON_OFF raw status interrupt.

RTC_TMR_INT_INT1_RAW_STATUS_FLAG: OFF_ON raw status interrupt.

RTC_TMR_INT_STATUS_ALL: All interrupt status mask.

RTC_TMR_INT_CLEAR_ALL: All interrupt clear mask.

RTC_TMR_INT_REQ_ALL: All interrupt set mask.

RTC_TMR_INT_RAW_STATUS_ALL: All interrupt raw status mask.

Defines

OSCILLATOR_FREQ_HZ: 32.768 kHz Crystal Oscillator Frequency

RTC_FREEZE_MODE: Enable Freeze Mode.

O32K_OSC_DEP_EN_MASK: O32K_OSC_DEP_EN_MASK.

RD_PEND_MASK: Read Pend Status.

WR_PEND_MASK: Write Pend Status.

O32K_CLK_OBS_BIT_MASK: O32K_CLK_OBS_BIT_MASK.

RTC_SW_OFF_MASK: RTC_SW_OFF_MASK.

RTC_UNLOCK_MASK: Unlock State Status.

OSC_LOCK_WAIT: Wait time for stabalizing OSC.

KICK0_UNLOCK_VALUE: RTC Kick unlock values.

KICK1_UNLOCK_VALUE

KICK0_LOCK_VALUE: RTC Kick lock values.

KICK1_LOCK_VALUE

RTC_BASEADDR: RTC Base Address.

Typedefs

typedef struct RTC_Config_s *RTC_Handle: A handle that is returned from a RTC_open() call.

typedef void (*RTC_OnOffCallbackFxn)(RTC_Handle handle)

The definition of a ON_OFF callback function used by the RTC driver.

The callback will be called if the ON_OFF interrupt is enabled.

Param handle:: RTC_Handle

typedef void (*RTC_OffOnCallbackFxn)(RTC_Handle handle)

The definition of a OFF_ON callback function used by the RTC driver.

The callback will be called if the OFF_ON interrupt is enabled.

Param handle:: RTC_Handle

Functions

void RTC_init(void): Initialize the RTC module.

void RTC_deinit(void): De-initialize the RTC module.

void RTC_paramsInit(RTC_Params *params)

Function to set default values of RTC_Params in params.

Parameters:: params – [IN] pointer to the structure to be initialized

RTC_Handle RTC_open(uint32_t idx, const RTC_Params *params)

Open the RTC at index idx with parameters params.

Parameters:

idx – [IN] Index of RTC to open in global config
params – [IN] RTC_Params values to use for opening

Returns:

RTC_Handle

void RTC_close(RTC_Handle handle)

Function to close the RTC Peripheral specified by the handle.